diff --git a/web/src/main/java/org/springframework/security/web/authentication/AbstractAuthenticationProcessingFilter.java b/web/src/main/java/org/springframework/security/web/authentication/AbstractAuthenticationProcessingFilter.java
index 8539aefa86..5d9ccd41ca 100644
--- a/web/src/main/java/org/springframework/security/web/authentication/AbstractAuthenticationProcessingFilter.java
+++ b/web/src/main/java/org/springframework/security/web/authentication/AbstractAuthenticationProcessingFilter.java
@@ -317,7 +317,7 @@ public abstract class AbstractAuthenticationProcessingFilter extends GenericFilt
         if (logger.isDebugEnabled()) {
             logger.debug("Authentication request failed: " + failed.toString());
             logger.debug("Updated SecurityContextHolder to contain null Authentication");
-            logger.debug("Delegating to authentication failure handler" + failureHandler);
+            logger.debug("Delegating to authentication failure handler " + failureHandler);
         }
 
         rememberMeServices.loginFail(request, response);